Its the bulb, they are $175 from Lexus or you can go with an after market bulb.

 

Had the same problem about a year ago. Replaced bulbs with XenonDepot bulbs and all was well again.

 

I am having a same issue on my 07 IS350 with 87K miles passenger low beam light goes out and if I turn lights off then back on the passenger side works again for unknown amount of time as it is random and usually I have to drive the car. I need to know how do you tell what kind of bulb you have and websites that are good for a replacement bulb or set I see others talk about Xenon Depot but when I do a google search on it nothing shows up for a webiste, but I get other parts companies instead. I am new to Lexus and need a guiding push in the right direction. Please post how to tell what kind of bulb I would have or how to tell and parts sites that I can check for replacement? Thanks

 

http://www.kbcarstuff.com/D4S-HID-Bulbs-s/9436.htm

 

The OEM bulbs are philips right guys? I want to try and stick with OEM because its what I like. Im not into the crazy HID bulb upgrades with all the color varations

 

yes the OEM HID bulbs are phillips 4300k. xenon depot will run you $70 for a replacement. this is why i decided to add just a tad bit more white/blue to mine and go with xenot depot's bulbs (which have good reviews) in 6500k. it was $100 for the pair with the CL discount. i think they had closer to OEM color temperatures as well. I just didn't want to install one new bulb with one that has 4 years of use already out of fear of color variation.

as long you stay between 4300k and 6500k you shouldn't have any problems. it's once you start going to 8000k and higher that you get super blue colored headlights.

 

OEM used to be Philips (before 2008), they are now Toshiba-Harison.

Jeff

 

Thanks for the information I just bought the D4S bulbs to replace the one that is going out, maybe, I wish there was a way to know if there is an issue with the ballistc.

 

If the bulb doesn't fix it, it's likely the ballast

More often than not it's the bulb though.

 

I'm having the same problem. Hope a new bulb will work. Let me know if it works for you.

 

Same thing my bulb did when it was going out. Might be good to check the wiring as well.

 

I will post once the bulbs get to home, I plan on replacing both that way no color difference and I will check all wiring at the same time. As far as the Ballast I have seen one YouTube video of a guy with a 07 IS250 taking the headlight assembly out and using a heat gun to melt the glue to take the lens off to replace the Ballast, is that correct if anyone knows, that just sounds very harsh way of getting to the Ballast instead of going through some bolts or screws and a gasket, any URL's or other videos if I have to buy a Ballast just in case?

 

I have the bulbs now (Philips D4S 42402, Original equipment Xenon Standard, D4S 42V 35W P32d-5: as per the box) I will install the bulbs either today or tomorrow, how ever after researching some articles here and other sites I found the following:
https://www.clublexus.com/forums/lig...for-is250.html

Could there be possible issues with the D42 bulbs, has anyone else run into this issue of having to go through several bulbs to fix the headlight going out? I have seen where replacing the ballast is a pain in the rear as you have to melt the glue and take off the headlamp cover to get to the interior wiring of the unit and replacement unit of the entire headlamp can cost $500 and up to over a grand for the 2013 headlamp upgrade.

 

the bulbs will likely fix the problem. my new bulbs came in this week and both lights work just fine now.

in the link you posted, i'm guessing the OP got bad bulbs from ebay that were not actually OEM Philips bulbs but knockoffs.

as long as you got your bulbs from xenon depot, you SHOULD be good to go once you install the bulbs.

 

I had the same issue, my friend happened to have 2 new headlights so i just took his and replaced my entire headlight.